Hydrocarbon-producing wells often are stimulated by hydraulic fracturing operations, wherein a fracturing fluid may be introduced into a portion of a subterranean formation penetrated by a wellbore at a hydraulic pressure sufficient to create or enhance at least one fracture therein. Stimulating or treating the wellbore in such ways increases hydrocarbon production from the well. Fractures are formed when a subterranean formation is stressed or strained.
In some instances, where multiple fractures are propagated, those fractures may form an interconnected network of fractures referred to herein as a “fracture network.” In some instances, fracture networks may contribute to the fluid flow rates (permeability or transmissability) through formations and, as such, improve the recovery of hydrocarbons from a subterranean formation. Fracture networks may vary in degree as to complexity and branching.
Fracture networks may comprise induced fractures introduced into a subterranean formation, fractures naturally occurring in a subterranean formation, or combinations thereof. Heterogeneous subterranean formations may comprise natural fractures which may or may not be conductive under original state conditions. As a fracture is introduced into a subterranean formation, for example, as by a hydraulic fracturing operation, natural fractures may be altered from their original state. For example, natural fractures may dilate, constrict, or otherwise shift. Where natural fractures are dilated as a result of a fracturing operation, the induced fractures and dilated natural fractures may form a fracture network, as opposed to bi-wing fractures which are conventionally associated with fracturing operations. Such a fracture network may result in greater connectivity to the reservoirs, allowing more pathways to produce hydrocarbons.
Some subterranean formations may exhibit stress conditions such that a fracture introduced into that subterranean formation is discouraged or prevented from extending in multiple directions (e.g., so as to form a branched fracture) or such that sufficient dilation of the natural fractures is discouraged or prevented, thereby discouraging the creation of complex fracture networks. As such, the creation of fracture networks is often limited by conventional fracturing methods. Thus, there is a need for an improved method of creating branched fractures and fractures networks.